1. Field of Invention
The present invention relates generally to the field of communications systems, and, more particularly in one exemplary aspect to wireless systems that allow user equipment to authenticate to wireless networks (e.g., cellular networks, WLANs, etc.) using access control clients.
2. Description of Related Technology
Access control is required for secure communication in most prior art wireless radio communication systems. As an example, one simple access control scheme might comprise: (i) verifying the identity of a communicating party, and (ii) granting a level of access commensurate with the verified identity. Within the context of an exemplary cellular system (e.g., Universal Mobile Telecommunications System (UMTS)), access control is governed by an access control client, referred to as a Universal Subscriber Identity Module (USIM) executing on a physical Universal Integrated Circuit Card (UICC). The USIM access control client authenticates the subscriber to the UMTS cellular network. After successful authentication, the subscriber is allowed access to the cellular network. As used hereinafter, the term “access control client” refers generally to a logical entity, either embodied within hardware or software, suited for controlling access of a first device to a network. Common examples of access control clients include the aforementioned USIM, CDMA Subscriber Identification Modules (CSIM), IP Multimedia Services Identity Module (ISIM), Subscriber Identity Modules (SIM), Removable User Identity Modules (RUIM), etc.
Traditionally, the USIM (or more generally “SIM”) performs the well known Authentication and Key Agreement (AKA) procedure, which verifies and decrypts the applicable data and programs to ensure secure initialization. Specifically, the USIM must both (i) successfully answer a remote challenge to prove its identity to the network operator, and (ii) issue a challenge to verify the identity of the network.
When a SIM card is manufactured, the SIM card is programmed with carrier-specific authentication information that restricts the use of that SIM card to a particular carrier. If a user wishes to change services from the existing carrier to a new carrier, the user needs to replace their SIM card with a new SIM card programmed in a similar way, but for the different carrier.
However, existing SIM solutions have multiple weaknesses and shortcomings. For example, the SIM software is hard-coded to the physical SIM card media; consequently, subscribers need new SIM cards to change SIM operation. In an effort to reduce the inconvenience of swapping cards, some cards are preloaded with two accounts. The user can switch between the two accounts without physically removing the card. However, the user of this type of SIM card will still need a new card to add new accounts.
Similarly, some user devices have multiple card slots; however, supporting multiple card receptacles is bulky, and none-the-less requires an actual SIM card for operation. Moreover, in the event of loss of either the SIM card, or the device containing the SIM card, the user must obtain a new SIM card in order to restore access to the associated account.
Thus, improved solutions are required for managing and accessing wireless services. Ideally, such solutions should not rely on a physical card for access control. Moreover, the improved solutions should be compatible with or support other desirable features such as, e.g., multiple access control profiles, backup of various profiles, remote storage of access control profiles, etc.